For at least the third time this year, Senate Democratic Majority Leader Harry Reid is threatening the “nuclear option” to filibuster reform after he extracted minor victories in January and July employing the same tactic.

Sen. John McCain (R-Ariz.) told TIME that he has been in discussions with the Democratic leadership, a role revisited multiple times from at least 2005 through this year. Reid rejected an offer by McCain Wednesday, according to an aide familiar with the discussions, since the proposal did not allow the Senate to move forward to allow a vote on all three of President Obama’s nominees to the U.S. Court of Appeals for the D.C. Circuit. Over the past three weeks, Republicans have filibustered the nominations.

“Stay tuned over the next 24 hours,” McCain said, who noted that he takes the new rhetoric “seriously, but I’ve heard it a couple of times before.”

The “nuclear option,” which the Senate has never used, forbids the minority from using its only real power to extract concessions: stalling. Reid’s plan, according to Senate Democratic leadership aides, is to use the “nuclear option” to eliminate the filibuster on confirming non-Supreme Court judicial and executive branch nominees. Sens. Barbara Boxer (D-Calif.) and Diane Feinstein (D-Calif.) support the proposal despite their prior opposition to the tactic, increasing the likelihood that Reid can get the 51 votes he needs. There are 55 Senators who caucus with the Democrats.

The D.C. Circuit Court of Appeals has outsize influence reviewing many of the cases involving federal administrative agencies, and four of the nine Supreme Court Justices have served on the court. The eight active judges on the court are split evenly by party ideology, although Republicans appointed five of six senior status judges, who sometimes hear cases.

The Republicans, taking a page from the Democrats’ playbook during the Bush Administration, say the filibusters aren’t due to the candidates’ qualifications, but because they believe the court is underworked. “That was exactly the position of the Democratic Senators in 2006 and 2007,” said Sen. Lamar Alexander (R-Tenn.) on the chamber floor Wednesday. Indeed, a 2006 letter signed by Democratic Senators on the Judiciary Committee—including Vice President Biden and current Sens. Chuck Schumer (D-NY), Patrick Leahy (D-VT), Dick Durbin (D-Ill.), Diane Feinstein (D-Calif.)—argued that they should debate the necessity of filling an 11th seat before turning to President George W. Bush‘s nominee Peter Keisler.

In their letter, the Democrats quoted Republican Senators who had previously supported the position that the court did not need 11 judges—including Jeff Sessions (R-Ala.) and Chuck Grassley (R-Iowa)—in 1997.

But the Democrats and Republicans believe this time is different. Democrats have grown exasperated by the slow nomination process, which is in part due to Obama’s slower than usual submissions. Democrats ire, however is naturally on Republicans: besides the three court nominations, Republicans earlier this month blocked the nomination of Rep. Mel Watt (D-N.C.) to the Federal Housing Finance Agency.

For the congressional black caucus, the partisan dismay has turned to claims of racism. Rep. Charles B. Randel (D-NY) told Roll Call this week that if Republicans “were ever able to track down their ancestors, there’s a Confederate general in every damn living room.” Robert L. Wilkins, a court nominee, and Watt are both African Americans. Republicans have denied the claim.